Purpose: To investigate the utility of MRI measurement of left atrial (LA) flow patterns and turbulent kinetic energy (TKE) in patients with clinically significant mitral regurgitation. Materials and Methods:Three-dimensional cine phasecontrast MRI (PC-MRI) data were acquired in five patients with posterior mitral leaflet prolapse and two normal volunteers. LA flow patterns were assessed using particle trace visualization. Specifically, vortices were recognized by closed streamlines. LA flow distortion was assessed by estimation of TKE. In addition, the regurgitant volume was measured.Results: Four of the mitral regurgitation patients had eccentric regurgitant jets directed toward the septum; one patient had a central jet. The dominant systolic vortex was located in proximity to the regurgitant jet. The LA flow was highly disturbed with elevated values of TKE; peak LA TKE ranged from 13 to 37 mJ and occurred consistently at late systole. The average LA TKE per cardiac cycle was significantly related to the regurgitant volume (TKE ¼ 0.573 þ 0.179ÁRegVol, R 2 ¼ 0.983).Conclusion: MRI permits investigations of atrial flow patterns and TKE in significant mitral regurgitation. The degree of LA flow distortion, as measured by the average LA TKE over one cardiac cycle, appears to reflect the severity of regurgitation.

OBJECTIVE: The indications for and the risk and benefit of concomitant surgical ablation for atrial fibrillation (AF) have not been fully delineated. Our aim was to survey whether the Cox-maze IV procedure is associated with postoperative heart failure (PHF) or other adverse short-term outcomes after mitral valve surgery (MVS). DESIGN: Consecutive patients with AF undergoing MVS with (n = 50) or without (n = 66) concomitant Cox-maze IV cryoablation were analysed regarding perioperative data and one-year mortality. RESULTS: The patients in the Maze group were younger, were in lower NYHA classes, had better right ventricular function and had lower pulmonary artery pressure. The Maze group had 30 min longer median cross-clamp time (CCT) and 50% had PHF compared with 33% in the No-maze group, p = 0.09. Two patients in the No-maze group died within one year of surgery. Congestive heart failure (OR 4.3 [CI 95%: 1.8-10], p < 0.0001) and CCT (OR 1.03 [CI 95%: 1.01-1.04], p = 0.001) were associated with PHF. CONCLUSION: The current data cannot exclude that concomitant cryoablation increases the risk for PHF, possibly by increasing the cross clamp time.

Funding agencies: ALF funding, County Council of Ostergotland, Sweden

BackgroundAtrial linear scars in Cox‐Maze IV procedures are achieved using Cryothermy (Cryo) or radiofrequency (RF) techniques. The subsequent postoperative left atrial (LA) reverse remodelling is unclear. We used 2‐ and 3‐dimensional echocardiography (2‐3DE) to compare the impact of Cryo and RF procedures on LA size and function 1 year after Cox‐maze IV ablation concomitant with Mitral valve (MV) surgery.MethodsSeventy‐two patients with MV disease and AF were randomized to Cryo (n = 35) or RF (n = 37) ablation. Another 33 patients were enroled without ablation (NoMaze). All patients underwent an echocardiogram the day before and 1 year after surgery. The LA function was assessed on 2D strain by speckle tracking and 3DE.ResultsForty‐two ablated patients recovered sinus rhythm (SR) 1 year after surgery. They had comparable left and right systolic ventricular function, LA volume index (LAVI), and 2D reservoir strain before surgery. At follow‐up, the 3DE extracted reservoir and booster function were higher after RF (37 ± 10% vs. 26 ± 6%; p < 0.001) than Cryo ablation (18 ± 9 vs. 7 ± 4%; p < 0.001), while passive conduit function was comparable between groups (24 ± 11 vs. 20 ± 8%; p = 0.17). The extent of LAVI reduction depended on the duration of AF preoperatively.ConclusionsSR restoration after MV surgery and maze results in LA size reduction irrespective of the energy source used. Compared to RF, the extension of ablation area produced by Cryo implies a structural LA remodelling affecting LA systolic function.

Background: Surgical cryothermia and radiofrequency (RF) ablations for atrial fibrillation (AF) seem to result in similar sinus rhythm restoration, but the biochemical consequences of the two methods are unclear. We aimed to compare the biochemical responses to the two ablative methods in concomitant mitral valve surgery (MVS). Methods: Sixty mitral valve surgery patients with AF were prospectively included. Forty-one patients planned for ablation were randomized to cryothermia (n = 20) or radiofrequency (n = 21) ablation and 19 served as controls. Markers for myocardial injury, inflammation, cell stress, apoptosis, and heart failure were analyzed pre-and postoperatively at different time points. Results: Troponin T and creatine kinase isoenzyme MB (CK-MB) peak levels were significantly higher in the cryothermia group compared with the RF group (12,805 [6140-15,700] vs. 2790 [1880-4180] ng/L; P = 0.002 and 271 [217-357] vs. 79 [66-93] μg/L; P < 0.001, respectively). Both groups had significantly higher levels than the noablation group. There were no group differences in C-reactive protein (CRP) and N-terminal pro-B-type natriuretic peptide (NT-proBNP), but there were correlations between pre-and postoperative levels of both CRP (r s = 0.41, P = 0.001) and NT-proBNP (r s = 0.48, P < 0.001). Protease-activated receptor 1 (PAR-1) and heat shock protein 27 (HSP27) were significantly increased in the cryoablation group. Conclusions: Cryoablation results in a larger myocardial injury and possibly more elevated apoptotic activity and cell stress compared with the RF technique. The type of ablation device did not have any significant influence on the postoperative inflammatory response nor on the early postoperative levels of NT-proBNP.

Background The Cox maze procedures have been shown to be safe methods for restoring sinus rhythm (SR) in patient with atrial fibrillation and often performed concomitant to mitral valve (MV) surgery. Cryothermy (Cryo) and Radiofrequency (RF) are available techniques to achieve atrial linear scars. The differences between the effect of these energy sources on late left atrial (LA) reverse remodeling are not fully described. Purpose This study aims to compare the impact of Cryo and RF procedures on left atrial (LA) size and function one year after Cox-maze IV concomitant to MV surgery using 3-dimensional echocardiography (3DE). Methods Seventy-two patients with MV disease and atrial fibrillation were randomized to either Cryo (35) or RF (37) ablation. Another 33 patients were enrolled according to the protocol without concomitant ablation (NoMaze group). All patients had an echocardiogram before and one year after surgery. Results The 42 ablated patients who recovered sinus rhythm (SR) one year after surgery had comparable left and right systolic ventricular function and a mean reduction of LA size by 23% (LA volume index decreased from 66±24 to 54±13ml/m2, p=0.004). The 3DE extracted reservoir and booster function showed higher values after RF ablation compared to Cryo (37±10% vs 26±6%; p&lt;0.001 resp. 18±9 vs 7±4%, p&lt;0.001), while passive conduit function was comparable (24±11 vs 20±8%; p=0.17). Patients with restored SR without ablation had more preserved systolic atrial function but similar LA size reduction as those who underwent maze surgery. Conclusions SR restoration after MV surgery and maze results in LA size reduction irrespective of the energy source used. By 3DE we could show that, compared to RF maze, the extension of ablation area produced by Cryo implies a major LA structural remodeling affecting LA systolic function. The reverse size remodeling seems to be the least, the longer AF history. Funding Acknowledgement Type of funding sources: Public grant(s) – National budget only. Main funding source(s): ALF funding for clinical research-Sweden